(a) Field of the Invention
The present invention relates to a power converter. More particularly, it relates to a power converter that controls a burst voltage, and a switching controller and a driving method of the power converter.
(b) Description of the Related Art
A power converter, for example a switching mode power supply (SMPS), rectifies an input AC voltage to an input DC voltage and converts the input DC voltage to a DC output voltage having a different level. The power converter is mainly applied to electronic devices, for example power supply devices such as a mobile phone, a computer, and a television.
The electronic device has a normal operation mode that consumes a relatively large amount of power and a standby mode that consumes a relatively small amount of power.
The power converter performs a burst mode operation that performs a switching operation of the power converter for a predetermined time period according to a feedback voltage in order to reduce power consumption during the standby mode, and then stops the switching operation for a predetermined time period. For this, the power converter determines whether to perform the burst mode operation by comparing the feedback voltage with a burst reference voltage.
When a current limit value of a current flowing to a switch of a primary side of a transformer can be determined, the power converter can be newly designed by changing the current limit value, and in this case, a feedback voltage of the new power converter is changed compared to that of a conventional power converter. In this condition, whether to perform the burst mode operation is determined by comparing the feedback voltage with the burst reference voltage, and the burst operation cannot be performed at a desired load due to the changed feedback voltage.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.